X-ray Astronomy
Major Milestones
X-ray Universe
X-rays & Light
VS. Medical X-ray
X-ray Absorption
X-ray Images 101
Galactic Navigation
Dark Matter
Dark Energy
Chemistry & Cosmos
X-ray Sources
Solar System
White Dwarfs
Neutron Stars
Black Holes
Quasars & AGN
Galaxy Clusters
X-ray Background
Brown Dwarfs
Gamma Ray Bursts
Web Shortcuts
Chandra Blog
RSS Feed
Email Newsletter
News & Noteworthy
Image Use Policy
Questions & Answers
Glossary of Terms
Download Guide
Get Adobe Reader
The Reflection of Optical and X-Ray Platforms Striking Conventional Telescope Mirror

How do X-ray telescopes differ from optical telescopes? (java enhanced)

X-rays do not reflect off mirrors the same way that visible light does. Because of their high-energy, X-ray photons that strike a mirror directly will penetrate into the mirror in much the same way that bullets aimed directly at a surface will bury themselves in it. Likewise, just as a bullets can ricochet off a surface when they hit it at a grazing angle, so too will X-rays ricochet off mirrors if they hit at very shallow angles, like a stone skipping across the surface of a pond. These properties mean that X-ray telescopes must be very different from optical telescopes.

Chandra's Mirrors
Schematic of the Chandra mirror

The Chandra mirrors look more like barrels than the familiar dish shape of optical telescopes. Four 'mirror' shells are nested inside one another to increase the total reflecting area of the telescope. The inner, reflecting surfaces of the mirrors have to be precisely shaped, and aligned nearly parallel to the incoming X-rays. The mirrors focus X-ray photons onto state-of-the-art detectors which record position, and in some cases the energy, of the photons. These X-ray data are then analyzed and reconstructed into images of the celestial objects that produce the emissions.

page 1 2